פרסומים

Two distinct groups of macromol. inhibitors of Ca oxalate pptn. were found in the urine of healthy humans; one is \textgreater10,000 daltons, and the other is \textgreater500 but \textless1,000 daltons. The \textgreater10,000 dalton group was absent from the urine of stone formers. The data agrees with the hypothesis that several kinds of inhibitors are present in urine. [on SciFinder(R)]

The effects of solvent on the transition kinetics of polymorphic modifications of stearic acid were examd. in polar and nonpolar solns. Two typical polymorphs, B (low-temp. stable) and C (high-temp. stable), and the solvents (butanone, methanol, n-hexane, and decane) were studied. In all solns. the transitions from B to C and from C to B took place at temps. above and below 32°, at which the free energies of B and C have the same value, resp. The rates of the C → B transition were significantly dependent both on temp. and solvent. First, the transition rate was fastest between 22 and 26°. This was due to 2 conflicting factors; the free energy difference between B and C which decreases as the temp. approaches 32°, and the rates of dissoln. of C and growth of B which increase with temp.. Secondly, the solvent exclusively influenced the C → B transition; polar solvents, esp. methanol, caused a significantly more rapid transition than nonpolar solvents, the rates being relatively higher than those prediced by the soly. values. It was inferred that the different growth units (monomers in the polar solvents and dimers in the nonpolar ones) and the twisted lateral interface structures of the B polymorph would be responsible for the present solvent effect. [on SciFinder(R)]

Human blood leucocytes generate large amounts of superoxide following stimulation by polyarginine, polyanetholesulphonate and mixtures of a variety of soluble agents. Generation of O2-. by the various "cocktails" of soluble ligands is markedly enhanced by cytochalasins A, B, C, D, E and F. The efficiency of cytochalasin A is, however, at least 50-fold greater than that of the other cytochalasins. Leucocytes that have been treated for a few minutes with the cytolytic agents saponin, digitonin and lysolecithin undergo lysis and lose their superoxide-producing capacities, when a variety of soluble ligands are employed to stimulate superoxide production. A partial reactivation of the superoxide-producing capacities of the leucocytes can be achieved by adding NADPH. However, as the concentration of the cytolytic agents increases, reactivation of the cytochrome C reduction is less inhibitable by SOD, suggesting that cell lysis releases reductases of cytochrome C not connected with the superoxide-producing system of the leucocytes. Both saponin and digitonin can totally replace polyarginine as ingredients of the "cocktail," suggesting that these agents may also function as "priming agents" for superoxide production which can, however, further be enhanced by the addition of mixtures of soluble agents. Thus, leucocytes which had been lysed by membrane-active agents can nevertheless produce superoxide if adequate amounts of NADPH are added.

The effect of primary emulsifier concn. (Span 80) in a system contg. Tween 80, mineral oil, and H2O on H2O transport due to an osmotic gradient was studied by a Coulter counter method. Diln. of W/O/W emulsions with dil. NaCl caused a decrease in multiple drop diam. due to loss of internal H2O. The primary mechanism appears to be micelle transport. [on SciFinder(R)]

Treatment with phosphates, thiazides and allopurinol was undertaken in 54 idiopathic calcium oxalate stone formers, 38 of whom were recurrent stone formers. The patients were followed up for 1 1/2 to 4 years (mean 2.6). During the same period at the pre-treatment stage the patients formed 80 stones, but during therapy only one stone was formed. A dynamic scheme of therapy was used. Each patient was tested before the start of drug treatment by the discriminant index (DI) method, which measures the overall inhibitory potential to calcium oxalate crystallisation. About 10 days after the start of treatment the DI was tested again. If the response was positive, therapy was continued; if not, the patient was given another drug. Adjustments were made as required. The stopping of stone formation correlated well with the DI prediction but less well with the hypocalciuric effect of the drugs.[on SciFinder (R)]

In a terminological note with the title, “The Possessive Relation Marker in Coptic” (Enchoria 12:191–193, 1984), P. Swiggers criticizes and corrects the conventional designation “possessive article” or “possessive prefix” for ⲡⲁ-/ⲧⲁ-/ⲛⲁ- “he/she/they of-” and, much less explicitly, ⲡⲉϥ- “his”. Following several arguments meant to establish that these morpheme set(s) are “neither an article, nor a prefix”, Dr. Swiggers offers to replace the current terms with a new one, namely “possessive relation-marker”, presumably for both ⲡⲁ- and ⲡⲉϥ-.